A yarn winder for winding a running yarn around a rotating bobbin while traversing the yarn comprises a yarn traverse guide for guiding and traversing the running yarn in the axial direction of the bobbin. As one of yarn traverse guides, known is a yarn traverse guide having two free rollers (free rotating rollers) disposed in parallel to each other through a clearance between them, for controlling the running of a yarn against the force acting on the yarn in the yarn running direction (tension) and the force acting on the yarn in the traverse direction.
In this yarn traverse guide, the yarn running toward the winding bobbin passes through the clearance between the two free rollers, and the two free rollers are traversed in the axial direction of the winding bobbin, to traverse the running yarn in the axial direction of the winding bobbin while the yarn is wound around the winding bobbin.
However, this yarn traverse guide has a problem that the operation of introducing the yarn into the yarn traverse guide is very difficult. To address this problem, a yarn traverse guide comprising a ring guide and two free rollers disposed in parallel to each other through a clearance between them is proposed in Patent Document 1. The ring guide has an opening communicating from outside to inside the ring guide at the position corresponding to the clearance between the two free rollers. The yarn is introduced from the opening into the clearance between the two free rollers.
This conventional technique has greatly improved the convenience of introducing the yarn into the yarn traverse guide. However, with this conventional technique, if the force in the yarn running direction or the force in the direction crossing the yarn running direction but different from the traverse direction (hereinafter this direction is merely called the direction different from the traverse direction) acts on the yarn, the position control of the running yarn by the yarn traverse guide cannot be performed. That is, the conventional technique has a disadvantage that the yarn can deviate from the yarn traverse guide, not being able to be traversed any more.
In recent years, especially a turret (revolving) type yarn winder as proposed in Patent Document 2 is popularly used. With the turret (revolving) type yarn winder, in the turret (revolving) movement or yarn cutting by a cutter when the yarn is transferred from a fully loaded bobbin to an empty bobbin, the yarn deviates from the yarn traverse guide, since the force in the axial direction of the free rollers acts on the yarn. If this phenomenon occurs, there arise such problems that the yarn deviating from the yarn traverse guide and running toward the fully loaded bobbin is kept in sliding contact with the frame of the winder, to be damaged and that the cutting of the yarn by the cutter for transferring the yarn to an empty bobbin cannot be performed.
On the other hand, Patent Document 3 proposes a yarn traverse guide capable of relatively stably controlling the yarn passage, namely, a yarn traverse guide that allows stable yarn traversing without causing the yarn to deviate from the yarn traverse guide even if the force in the yarn traveling direction and the force in the direction different from the traverse direction act on the yarn.
In this yarn traverse guide, a yarn disengagement prevention hook crossing a yarn arresting groove formed near a yarn guide portion is provided near the opening of the yarn arresting groove. If this yarn traverse guide is used, the yarn can be stably traversed without deviating from the yarn traverse guide even if the force in the yarn running direction and the force in the direction different from the traverse direction act on the yarn. However, the yarn traverse guide has a problem that the operation of introducing the yarn into the yarn traverse guide is difficult, since the yarn disengagement prevention hook is obtrusive.    Patent Document 1: JP 58-123862 U    Patent Document 2: JP 05-193835 A    Patent Document 3: JP 02-132069 U